Since it's the beginning of the story, I'm not sure about the format. So here's a list of articles I went through for some GraphQL research I did for a client.
How to build a GraphQL API in Rails
Here's a very good explanation on how to build a GraphQL api in Rails published on Medium by Wayne Chu. Although it is a bit more than I needed for my research, I got a lot of value from reading this series of posts
More on GraphQL and rails
An very detailed wrap-up of the topic by Gaurav Tiwari. Again, a bit more than I needed in terms of the level of detail, but very helpful if you want to understand the end-to-end implications of using GraphQL.
And some example code, right here: https://github.com/gauravtiwari/graphql-server-examples/tree/master/ruby/rails_graphql
And an extra post from the same author: Zero to GraphQL — Building GraphQL servers in popular web frameworks
The long tail
These are the articles I skimmed through, except for Phil Sturgeon's article which has been recommended to me, which I read in its entirety.